Local Internet Protocol Access (LIPA) and Selected Internet Protocol Traffic Offload (SIPTO) as work items of the 3rd Generation Partnership Project (3GPP) Release 10 work items allow for installing a femto cell based station (Home evolved Node B (HeNB)) in a home network or enterprise network (or a network deployed by a third party operator (e.g., content provider and Internet service provider) cooperating with a mobile carrier) such that the traffic of a User Equipment (UE) connected through the femto cell is delivered to other devices of the home network or the enterprise network through a local gateway (L-GW) directly.
FIG. 1 is a diagram illustrating an LIPA network structure in which the HeNB and the L-GW are integrated according to the related art.
Referring to FIG. 1, the UE attached to the HeNB may connect to the outside Internet via a Serving Gateway (S-GW) and a Packet Data Network Gateway (P-GW) or to a local network via an L-GW. The L-GW is provided with an interface capable of connecting to the local network and is installed by the operator near the UE in order to reduce the traffic of the core network connected to the Internet.
In the radio network structure of FIG. 1, if the UE goes out of the service area of the HeNB, it is difficult to guarantee the session continuity. That is, when the UE moves out of the service area, the session connected previously to the local network ends to establish a new session so as not to guarantee the session continuity. In order to solve this problem, there is a need of a method for supporting inter-HeNB mobility of the UE.
In 3GPP release 11, LIPA mobility and SIPTO at the local network (LIMONET) is proposed as a new work item for providing the local network with a traffic offload function as well as guaranteeing the session continuity on the macro network. In the LIMONET, the L-GW and HeNB are deployed separately from each other as shown in FIG. 2. Accordingly, the UE can be handed over among the HeNBs connected to one L-GW.
FIG. 2 is a diagram illustrating the LIMONET architecture according to the related art.
However, the LIMONET can guarantee the session continuity in inter-HeNB handover but not in inter-L-GW handover. If the UE moves so as to be handed over between HeNBs connected to different L-GWs, the old session has to end before starting a new session. Since the UE roams without consideration of the locations of the L-GWs, inter-L-GW handover is likely to occur frequently so as to cause frequent session breakages, resulting in significant problem independently of the size of service area of the L-GW.
There is therefore a need of a method of enhancing the LIMONET function that is capable of guaranteeing session continuity even in inter-L-GW handover.
Meanwhile, a Content Delivery Network (CDN) is a network proposed for efficient contents delivery through traffic offload of Internet Backbone network and quick response time.
FIG. 3 is a signal flow diagram illustrating a data communication method in a network using a CDN server according to the related art.
Referring to FIG. 3, when the UE accesses a specific content server (e.g., YouTube), it acquires the page information including the Uniform Resource Locator (URL) of a content from the content server at operation 301. If the user clicks on certain content in the page at operation 303, the UE requests a Domain Name System (DNS) server for the Internet Protocol (IP) address corresponding to the domain name included in the URL of the selected content at operation 305. The DNS server sends the UE the IP address of the nearest CDN server, and the UE establishes a session with the CDN server at operation 307 and downloads the selected content from the CDN server at operation 309. Recently, the CDN service provider (e.g., Akamai) established a partnership with main global mobile carriers (e.g., AT&T, Orange telecom, and KT) to deploy CDN servers in the mobile communication networks of the mobile carriers. Accordingly, it is expected that the content servers and mobile communication networks are associated with each other more closely in the future when the 5th Generation (5G) mobile technology will be commercialized as compared with the present.
Meanwhile, the mobile carriers are preparing a new venture in which an eNB is equipped with a cache function for providing subscribers with CDN services. If the caching function is enabled at the eNB side, the eNB is capable of reading/writing files. However, the reading/writing is likely to be high load task for the eNB so as to cause processing overload. There is therefore a need of an efficient server management method for providing universal services such as file sharing and cloud services as well as CDN service.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.